Problem

Vista does not automatically write a daily restore point. Manually creating a restore point is possible.

Solution

The problem can lie in the scheduled task for the automatic restore points. If it is set to run only when the system is idle and you have some constantly running background task, even at low priority, the PC may
never be idle.

Change the scheduled task such that it is independent of the idle state. Over the next few days check whether restore points begin to appear.